Faster computation but less accurate near electrodes.
See also note on potentials, fields and contours near to boundaries.
The advantage of triggering this option is that the computing time is reduced. The disadvantage is that the potentials very near the electrodes are less accurate, which does not matter if the rays do not pass near the electrodes. So this option should usually be triggered.
Technique used by the program to improve the potentials near to segments:
In the BEM method used here the potential at the centre of a segment is exact, but the potential at other points on the surface of the segment tends to have a smaller magnitude. To correct the potential V at a general point P near to a segment, the program finds the nearest point N on the nearest segment and adds to V the difference D between the true voltage applied to the segment and the calculated potential at N. The program does this if the distance between P and the centre of the segment is less than 1.5 times the size of the segment (where size is defined as the distance from the centre of the segment to its farthest corner or end). If there is more than one segment within range then the program uses the corrections D due to all such segments, weighting the contributions by using the sizes of the segments and their distances of closest approach. Also the correction described above is ‘graded’ to try to give a smooth connection to the uncorrected ‘ordinary’ potentials that are outside the correction range.
See also note on outputting potential information and note on ray tracing).
The technique for improvement is automatically disabled when the option to import charges is in use, because then the potentials might not be related to the applied voltages. Similarly it is disabled when dielectric materials are present.
The option is enabled or disabled on the appropriate screen.